You are looking at the capacity factor for a whole year. Germans do not expect to get much solar for 6 months of fall and winter. Therefore, the German capacity factor in spring and summer is 2 x 10.2% = 20.4%. People living in the northern latitudes are happy to get their solar power in spring and summer. Northern Europeans are not competing with California, Arizona, New Mexico, Texas and the other southern states that have so much sunshine ready for solar panels.